Medical ethicists are reviewing an experimental Ebola virus treatment because it raises questions about whether untested medicine should be used on people according to the World Health Organisation (WHO).
In a statement the organisation said: "The gold standard for assessing new medicine involves a series of trials in humans, starting small to make sure the medicine is safe to use. Then, the studies are expanded to more people to see how effective it is, and how best to use it."
They added that the, "experimental medicine has raised questions about whether medicine that has never been tested and shown to be safe in people should be used in the outbreak and, given the extremely limited amount of medicine available, if it is used, who should receive it."
More than 160 staff will work in a UK-funded facility in Sierra Leone which is due to open in October.
UK trials of a vaccine for the Ebola virus began today - but some experts complain that the response has been a long time coming.
A Swansea doctor who took leave to treat Ebola patients in Africa, is back on the wards after three weeks in isolation.